Make sure you're using SparkiDuino, and not the vanilla Arduino
Alternatively, you can also install the boards for Sparki using the Arduino Board manager:
If you open up SparkiDuino and go to File > Preferences:
In the Additional Boards Manager Urls box, put in this:
Once you've done that, go to Tools > Boards > Board Manager.
With this open, select "ArcBotics Boards" (it might be at the bottom) and hit the install button that pops up in the lower-right. Your boards will re-appear.
If you accidentally installed an "update", you can reverse it by doing the following:
1.) Uninstall SparkiDuino
2.) Delete your arduino user files. They will be in your Documents folder, in a folder called "Arduino".
In windows, this is:
C:\Users\<Your User Name>\AppData\Local\Arduino15
In OSX, its your "Documents" folder in finder
3.) Re-download SparkiDuino from the Sparki start page:
The board should come back. (and automatic update prompts will now be disabled)